Rigid body cubes exploding when on floor
One easy solution is to add another plane which will be use only for collisions.


Turn off the rigid body on the floor you have now.
Add a new plane, and position it so that it is at (or sightly below) the top of the bumps on your original floor.
Add passive rigid body physics to the new plane.
Disable render of the collision only plane, by unticking the camera icon for it in the Outliner.